Creation and Evaluation of 3D Sectioned Pig Heart Models to Supplement Cardiac Ultrasound Training for Undergraduate Medical Students

The acquisition and interpretation of ultrasound scans require a thorough understanding of anatomy. Medical students learning ultrasound often struggle to visualize more complex and dynamic aspects of anatomy. In particular, novice sonographers find it challenging to understand the orientation of the heart in the body, its relationship to surface anatomy for probe placement, and its correlation to ultrasound images of the heart. The goal of this study was to determine if 3D physical heart models are an effective aide for helping students to interpret normal cardiac anatomy from B‐mode ultrasound. Using fixed pig hearts (preserved with Carolina's Perfect Solution), we created a total of six 3D‐sectioned models with three depicting parasternal long axis (PLAX) and three depicting parasternal short axis (PSAX) views. The pig hearts can be safely handled without the need for special ventilation, they are relatively inexpensive and easy to acquire, and are a suitable alternative to human hearts due to anatomical similarities. The sectioned pig hearts were provided to 114 out of the 184 students enrolled in medical gross anatomy at the University of Colorado. Students had the option to use the new models within a 1‐hour, small group, hands‐on, peer‐scanning thoracic ultrasound session. Using a voluntary, anonymous pencil‐and‐paper questionnaire, the students were surveyed immediately after the session to determine their attitudes toward the use of the sectioned pig hearts as an aide to learning sonographic anatomy of the heart. The survey contained three items: a forced‐response item asking if the heart models were used before live scanning, during live scanning, or both, and two Likert‐scale items rating the usefulness (1 = not useful; 5 = very useful) of the PLAX and PSAX‐sectioned pig heart models, respectively. After testing for normality, a two‐way ANOVA was performed to compare student views on the usefulness of PLAX versus PSAX models, and to compare usefulness ratings between student groups that used the models at different times. Survey response rate was 93% (n = 106 out of 114). Survey results indicated that nearly half of the students (45.3%) used the models both before and during live scanning, while half of students used them either only before (36.8%) or only during (17.9%) live scanning. An Anderson‐Darling (AD) test showed normal distribution of the Likert data. Survey responses indicated that 85% of students found the PLAX model useful to very useful (mean rating = 4.28 ± 0.74) and 80% found the PSAX model useful to very useful (mean rating = 4.21 ± 0.79) for learning cardiac ultrasound. Two‐way ANOVA results showed no significant difference ( p = 0.40) between the mean ratings for PLAX and PSAX usefulness within each temporal group, that is, students who used the models only before, only during, or at both intervals in the session. However, students that used the models both before and during scanning reported significantly higher mean usefulness ( p < 0.001) for both PLAX and PSAX models compared to students who used the models exclusively before or during scanning. These results indicate that medical students consider 3D sectioned PLAX and PSAX pig heart models useful as a teaching aide for cardiac ultrasound training. This study will be expanded by developing plastinated, sectioned human heart models to further supplement medical and anatomy student training in sonographic anatomy.